You can read here why pastured butter is better for you than butter from cows that are not grass-fed: http://aboutsalt.blogspot.co.uk/2010/08/have-you-ever-given-thought-as-to-which.html
And you can read here why butter is much, much, much, much, much better for you than margarine! - http://wildeaboutobesity.blogspot.co.uk/2010/12/butter-is-good-better-and-best.html
Maybe, like me, you were lured along the wrong path many years ago, but it is never too late to change to the healthier option. - Go on! - Give it a whirl!

